title: Cardiorespiratory fitness and adiposity in metabolically healthy overweight and obese youth.
abstract: OBJECTIVE
  Controversy exists surrounding the contribution of fitness and adiposity as determinants of the Metabolically Healthy Overweight(MHO) phenotype in youth. This study investigated the independent contribution of cardiorespiratory fitness and adiposity to the MHO phenotype among overweight and obese youth.
  
  
  METHODS
  This cross-sectional study included 108 overweight and obese youth classified as MHO (no cardiometabolic risk factors) or non-MHO (≥1 cardiometabolic risk factor), based on age- and gender specific cut-points for fasting glucose, triglycerides, high-density lipoprotein cholesterol, systolic and diastolic blood pressure, and hepaticsteatosis.
  
  
  RESULTS
  Twenty-five percent of overweight and obese youth were classified as MHO. This phenotype was associated with lower BMIz-score (BMI z-score: 1.8 ± 0.3 vs 2.1 ± 0.4, P = .02) and waist circumference (99.7 ± 13.2 vs 106.1 ± 13.7 cm, P = .04) compared with non-MHO youth. When matched for fitness level and stratified by BMI z-score (1.6 ± 0.3 vs 2.4 ± 0.2), the prevalence of MHO was four fold higher in the low BMI z-score group (27% vs 7%; P = .03).Multiple logistic regression analyses revealed that the best predictor of MHO was the absence of hepatic steatosis even after adjusting for waist circumference (odds ratio 0.57, 95% confidence interval 0.40–0.80) or BMI z-score (odds ratio 0.59, 95% confidence interval 0.43–0.80).
  
  
  CONCLUSIONS
  The MHO phenotype was present in 25% of overweight and obese youth and is strongly associated with lower levels of adiposity,and the absence of hepatic steatosis, but not with cardiorespiratory fitness.
authors.affiliation: Manitoba Institute of Child Health, Winnipeg, Manitoba, Canada.
authors.forename: Martin
authors.initials: M
authors.lastname: Sénéchal
authors.forename: Brandy
authors.initials: B
authors.lastname: Wicklow
authors.forename: Kristy
authors.initials: K
authors.lastname: Wittmeier
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Hay
authors.forename: Andrea C
authors.initials: AC
authors.lastname: MacIntosh
authors.forename: Pinar
authors.initials: P
authors.lastname: Eskicioglu
authors.forename: Niranjan
authors.initials: N
authors.lastname: Venugopal
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: McGavock
mesh_terms: D000293:Adolescent; D001823:Body Composition; D050218:Body Fat Distribution; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D004734:Energy Metabolism / Q000502:physiology*; D005234:Fatty Liver / Q000503:physiopathology; D005260:Female; D006293:Health Promotion; D006801:Humans; D008297:Male; D008350:Manitoba; D024821:Metabolic Syndrome / Q000175:diagnosis / Q000503:physiopathology; D009043:Motor Activity / Q000502:physiology; D009765:Obesity / Q000503:physiopathology*; D050177:Overweight / Q000503:physiopathology*; D010641:Phenotype; D010809:Physical Fitness / Q000502:physiology*; D012016:Reference Values; D012307:Risk Factors